Safety & Technical FAQs
Thermafleece is treated with a borax-based fire retardant. It passes the EN 11925 ignitability test, is Euroclass E rated, and complies with British Standard BS 5803-4 for flammability and resistance to smouldering.
The borax treatment is stable and intended to provide lifetime protection under normal dry service conditions.
The borax treatment helps prevent mould, but it is critical to keep humidity levels below 70-80%. Mould can grow on almost any surface if humidity remains persistently high.
Like all quilted insulation, Thermafleece will hold water like a sponge. It is recommended to remove the wet insulation and let the area dry completely before replacing it with new, dry material.
Lights: Lights marked “IC-F” or “IC” can be covered by insulation. For lights that cannot be covered, insulation must be kept at least 75mm away, and a fire hood should be installed. Always consult a qualified electrical engineer.
Cables: Where possible, electrical wires should not run through insulation. If they do, they must be sufficiently rated to handle the thermal environment. If you are not sure then consult a qualified electrical engineer.
Both CosyWool and UltraWool have a Euroclass E fire rating and pass BS5803 Pt4 for flammability and smoulder resistance.
They are not “non-combustible” and should not be used where non-combustible materials are legally mandatory.
No. Thermafleece cannot be installed in the void within brick and block or block and block cavity walls due to the high risk of waterlogging from driving rain.
